Bow contacts intended to transfer electrical currents between electrical conductors which move relative to one another generally have a carbon strip and a metal mounting. The purpose of the mounting and support is primarily to reinforce the carbon strips, the strength of which otherwise would not be able to resist the mechanical loads during operation. The carbon strips are often clamped into the mounting or connected to the mounting by rivets or bolts or screws. Since the known mechanical connections affect the fatigue strength of the carbon strips due to their notch effect, soldered and adhesive connections are used as an alternative to fasten the carbon strips on the mounting. For example, the carbon strip is bonded to a mounting in the form of a sheet-metal support using a synthetic-resin layer. The synthetic resin is applied to the lower side of the strip, which is provided in advance with a copper layer to improve current distribution, and to the sheet-metal mounting, the parts are joined and the synthetic-resin layers are cured. The electrical resistance of the connecting adhesive layer can be reduced by metal powders (DE 26 54 264 A1), which are embedded in the adhesive layer. A further improvement of the operating characteristics of bonded bow contacts can be achieved if the carbon strip surface and mounting surface to be bonded are roughened, coated with a diluted adhesive solution, electrically conductive particles are applied to at least one adhesive layer, the surfaces are pressed together and the adhesive layers are cured (EP 0 313 880 B1).
There is, however, still a continuing need to improve the long-term stability of the bow contact and the process reliability of its manufacture.